1. Field of the Invention
This invention relates in general to improvements to aircraft, particularly to improvements that reduce or suppress the vortices which trail from wing tips during flight.
2. Description of the Prior Art
Vortices are formed in the wake of airplanes during flight, including those vortices generated at the wing tips. When conditions are favorable, wing tip vortices are visible and susceptible to the collection of empirical data useful in analysis that may lead to correctional modifications.
An example of data collection following visulization may be seen in a report prepared by Ernest J. Cross, Jr., Phillip D. Bridges, Joe A. Brownlee and W. Wayne Livingston, "Full Scale Visualization of the Winged Tip Vortices Generated By A Typical Agricultural Aricraft", NASA Contract Report 159382, November 1980.
This report shows one form of a typical attempt to reduce or suppress wing tip vortices, the wing tip fence. The fence extends transversely in a vertical or oblique direction from the extremity of the wing tip. Various configurations have been proposed and are said to have beneficial effect, which has led to commercialization of at least one form, as indicated in FIG. 7 of the above NASA report. But the problem remains.
The problem manifests itself in several troublesome ways. Danger awaits the unwary in the trailing path of large, high speed jets. So severe is the turbulence and danger that small aircraft should not close within miles of the trailing path of a Boeing 747. Wing tip turbulence from agricultural aircraft disperses chemicals laterally beyond the intended path, sometimes with damaging consequences.